Electric tray



-Nov. 1, 1938.

E o. SESSIONS ELECTRIC TRAY Filed Jan. 5, L937 HIGH HEAT I47 MIN/W Low HEAT INVENTOR. EDSON O. Sass/0N5 ATTORNEY.

Patented Nov. 1, 1938 UNITED STATES PATENT OFFICE ELECTRIC TRAY Edson 0. Sessions, Chicago, 111.

Application January 5, 1937, SeriaiNo. 119,129

5 Claims.

My invention consists of a tray adapted for use in serving light lunches and similar purposes where it is desired to have heating facilities for different articles to be served. By my invention I provide a tray with a heating element or. elements and one or more electric outlet sockets connected by suitable wiring in the body' portion of the tray, so that the said electrical devices may be supplied with current by an electric cord and connecting plug constituting a part of the tray assembly. The tray is also provided with switching devices for selectively connecting desired ones of the electric devices in the circuit, and in this connection I find it desirable to arrange the switching devices so that ithe maximum electric load will not exceed the capacity of the fuses ordinarily employed in house lighting circuits. 7

The tray may be constructed of metal and ornamented as desired, either by the use of sheet metal, or cast metal, or if preferred, material of any suitable kind may be employed. My invention also includes electrically heated devices to be used with the electric tray and adapted for connection therewith and assembly thereon without the use of connecting wiring of any kind between said devices and the tray.

My invention will be best understood by reference to the accompanying drawing illustrating a preferred embodiment thereof in which Fig. 1 illustrates my tray in plan view,

Fig. 2 is a vertical, sectional view through th tray, taken longitudinally thereof along the line 2-2 in Fig. 1,

Fig. 3 is a vertical, sectional view through the tray shown in Fig. 1, taken along the line 3-3,

Fig. 4 is a vertical, sectional view to an enlarged scale of a part of the construction shown in Fig. 3, taken along the line 4-4, 1

Fig. 5 is a vertical, central, sectional view through the lower part of an electrically heated container, adapted to be used with the tray shown in Fig. 1,

Fig. 6 shows in front elevation and diagrammatically, a form of electric toaster adapted for use with the tray shown in Fig. 1, a part of the construction being shown in central, vertical, sectional view to better illustrate the electrical connecting devices, and

Fig. 7 is a diagrammatic circuit drawing of the electric connections employed in the tray illustrated in Fig. 1.

Similar numerals refer tosimilar parts throughout the several views.

As shown in Fig. 1, my electric tray consists of a body portion l0 made of any suitable material to impart the requisite strength and stability to the device, the material illustrated in the drawing being sheet metal, although it will be understood that the tray may be made of any other suitable material that is preferred in any case. The tray Ill is provided with-an edge rim ll extending somewhat above the horizontal supporting surface of thetray, and is also provided with feet I! to support it above any surface on which it may be placed. The tray in is provided with an-electrical heating element l3 having two heating coils l4 and IS, the coil 14 preferably develop ing a relatively large or high amount of heat, while the coil l5 preferably develops a relatively small or low amount of heat. The heating element I3 has disposed above it, a metal grill or grating IE to support above the heating element, any desired article or utensil to be heated, the upper surface of the grill being preferably substantially in the supporting surface of the tray Ill.

The tray Ill, is also provided as shown in Fig. 1, with two electrical and cylindrical outlet sockets l1 and I8 supported above the surface of the tray ill by annular flanges l9 and 20 surrounding them. Thefront portion of the tray has mounted thereon two electric switches 2| and 22 by which the flow of electric current to the heating coils l4 and I5 and to the sockets l1 and I8, may be controlled as desired.

As shown in Fig. 2 the bottom of the tray consists of a removable plate 23 of sheet metal or other suitable material which fits a recessed portion Illa of the tray structure, being held in place by screws 24 so that the wiring of the tray may be effected, there being suflicientspace between the bottom plate 23 and the top portion of the tray to permit this to be done. The upper portion of the tray at the location of the heatingelement I3, is provided with a downwardly extending annular portion lllb provided with vertically displaced shoulders, the lower one of which supports the heating element I3, and the upper one of which supports the grill it so that its upper surface is substantially inthe plane of the supporting surface of the tray. To guard against an undue amount of heat being communicated from the heating element [3 to the bottom plate 23 of the tray, I prefer to mount under the heating element and above the said bottom wall, a screen or shield 25 of metal or other suitable material, so that there is a first air space between the shield and the heating element l3, and a second air space between the shield and the bottom wall 23, through which spaces air may freely cirelectrical devices.

culate. Where the heat developed by the heating element I3 is considerable, I find it desirable to provide perforations 23a through the bottom plate 23, under the shield 25 to admit cooling air to the interior of the tray.

In Fig. 3, the relation of the flanges l8 and 20 to the upper portion of the tray I8 is more clearly shown, as well as the relation of the outlet sockets I! and I8 to said flanges. As shown in this figure, the top wall of the tray has secured thereto downwardly extending annular flanges 25 and 21 in line with the flanges l8 and 20, to re: ceive the lower end portions of the outlet sockets I1 and I8 with a free fit, the flanges 26 and 21 being in-turned at their lower edges to support the outlet sockets l1 and I8 against vertical thrusts downwardly that may be exerted upon them in electrically connecting with them, desired The sockets I! and I8 have extending into them, through corresponding annular slots in the flanges 26 and 21, pins 28 and 29, which pins prevent movement upwardly of the sockets relatively to said flanges, and at the same time permit a limited amount of angular motion of each socket relative to its supporting flanges, which feature of construction is more clearly illustrated for the socket IT in Fig. 4, it being understood that the sockets l1 and I8 are similarly constructed and held in place in the tray. As shown in Fig. 4, the pin 28 extends through an annular slot 28a through the flange 26, said slot having an angular extent of the amount which it is desired to permit the socket IT to move in using the tray, the amount of angular movement which I flnd convenient in practice, being from A to of the circumference of The pin 28 is a free fit in the slot 280,

the flange. so that the socket I! may be turned freely in its supporting flanges, to adapt the socket to the particular angular position of the device used with the socket, that is found most convenient in one use or another of the tray.

As shown in Fig. 5, I illustrate at 30 the lower part of a utensil adapted to be heated by electric connection with the tray, for example a coffee pot, the lower end of the part 30 being recessed and internally threaded, to receive corresponding external threads on a base portion 3|, which base portion is recessed at its upper end to receive and support a suitable electrical heating element 32. Below the heating element 32, the base 3| is provided with a second and smaller recess, containing a plate 33 of insulating material affording rigid support for the electrical plugs 34 contained in a recess 35 below the plate 33 and in the lower part of the base 3|, which recess 35 is open at its lower end and is of suflicient size to pass freely over the flanges I9 and 20 above described, so that the plugs 34 may enter the openings in either of the sockets I1 and I8 and make electrical connection therewith with the bottom surface of the base 3| resting on the upper surface of the tray. The plugs 34 are connected by wires 36 with the heating element 32. By having the upper ends of the sockets I1 and I8 in raised position above the upper surface of the tray I0 as above described, the plugs 34 may terminate abovethe bottom surface of the base of the utensil illustrated in Fig. 5, so that the said plugs will not interfere in any way with resting the utensil on any flat surface. Another advantage resulting from the raised position of the sockets I! and I8, is that crumbs on the tray are prevented from entering said sockets and creating electrical disturbances.

In using the utensil shown in Fig. 5 with either of the sockets I1 and I8, the position of the apertures in the socket is noted and the utensil is turned until the plugs 34 are in alignment with the socket apertures, and the utensil is then pressed downwardly, moving the plugs into electrical contact with theinternal contacts of the selected socket, until the base 3| rests on the upper surface of the tray, after which if the angular position of the utensil is not convenient, it may be turned to a position that is more convenient, depending upon the kind of utensil being used and whether the tray is being used from its side or its end.

In Fig. 6 I illustrate diagrammatically at 31, an electric toaster adapted for use with the tray shown in Fig. 1, which toaster is provided with a heating element 38 connected with plugs 38 mounted in a recess 40 in the base portion of the toaster, in which recess said plugs are held in vertical position by a block 4| of insulating material supported by and secured to the upper end of the wall of the recess 4|] as indicated. The recess 40 provides that the plugs 39 may be entirely contained above the bottom plane of the toaster 31, so as not to interfere in any way with supporting the toaster on a plane surface, the plugs 33 being adapted for connection with either of the sockets I! and I8 in the manner described above for the utensil shown in Fig. 5, the toaster being angularly adjustable as desired around the vertical axis of the connected socket, to suit the convenience of the user of the tray.

In Fig. '7, I illustrate diagrammatically the circuit connections which, with the embodiment shown in Fig. 1, are made in the interior of the tray between the electric cord 42, the heating coils I4 and I5, the outlet sockets I1 and .I8 and the switches 2| and 22, as follows:

Assuming that the plug 43 attached to the cord 42, is connected with suitable line wires, for example, of any ordinary house lighting system, line wire 44 is connected by wires 45 and 46 with one terminal of each of the plugs I1 and I8 respectively, and by a wire 41 with one terminal of each of the heating coils 4 and I5. The other terminal of the socket I1 is connected by a wire 48 with a contact 49 of the switch 2|, and the other terminal of the socket I8 is connected by a wire 5|! with a second contact 5| of said switch. The other terminal of the high heat coil I4 is connected by a wire 52 with a third contact 53 of the switch 2|, and the other terminal of the low heat coil I5 is connected by a wire 54 with a contact 55 of the switch 22, the blade portions of the switches 2| and 22 being connected together and with the other line wire 56. By controlling the sockets I! and I8 and the high heat coil |4 selectively by the switch 2|, it will be observed that it is impossible to connect more than one of said devices in circuit between the line wires 44 and 56 at the same time, so that if, for example, the electric devices intended for use with the outlet sockets I1 and I8 require not over 1,200 watts each to operate them, and the heating coil |4 requires not over 1,200 watts to operate it, as far as the switch 2| is concerned, it is impossible to connect a load of more than 1,200 watts with the line wires 44 and 56, thus insuring that the fuses used in house wiring for electrical utensils in common use, will not be overloaded. The low heat coil I5 is intended to use a relatively small amount of power as a result of its relatively high resistance, for example, about watts, and the switch 22 provides that the low heat coil |5 may be used at the same time as the high heat coil I 4 or as either of the outlet sockets l1 and it, if desired, or it may be used alone when, for example, it is desired to keep any articles or utensil warm. In this manner, the load on the line wires 44 and 56 may be controlled so as to not appreciably exceed the amount commonly required for a single electric toaster, a single electric flat iron, or other electrically heated device in common It will be understood that I do not limit myself to thearrangement of electrical devices illustrated with the tray, or to any particular utensils or appliances constructed to cooperate with the out let sockets of the tray, the construction shown in the drawing being illustrative of an embodiment of my invention which may be employed to meet general requirements. I do not, therefore, limit myself to the particular construction described. as I may employ equivalents thereof without departing from the scope of the appended claims.

What I claim is:

1. In an electric tray, the combination of a body apportion, an electrical heating element mounted in said body portion, electrical utensil outlet sockets spaced from each other and from said heating element and mounted in said body portion, said body portion being hollow, an electrical, connection cord extending from said tray, selective switching mechanism carried by said tray, and electrical conductors in said body portion andconnecting said sockets and said heating element with said cord and with said switching mechanism, whereby said sockets and said heating element may be selectively connected with said cord by said switching mechanism, said heating element including a low heat portion for connectioni with said cord independently of said selective connection.

2. In electric tray, the combination of a body portion, an electrical heating element mounted in said body portion, electrical utensil outlet sockets spaced from each other and from said heating element and mounted in said body portion, said body portion being hollow, an electrical connection cord extending from said tray, selective switching mechanism carried by said tray, and electrical conductors in said body portion and connecting said sockets and said heating element with said cord and with said mechanism, whereby said sockets and said heating element may be selectively connected with said cord. by said switching mechanism, said sockets having limited angular movement relals tively body portion, whereby a utensil connected with either of said sockets may be tinned a limited amount on the tray.

3. In an electric tray, the combination of a bodyportion, an electrical heating element supported by said body portion, electrical outlet sockets supported by said body portion for connection with separate electrically heated utensils, two electrical supply conductors, an electrical switch having spaced active contacts, first electric wires selectively connecting said active contacts with one terminal of each of said sockets andoi said heating element, and second electric wires connecting the other terminals of said sockets and of said heating element with a first one of supply conductors and also connecting the other of said supply conductors with said switch, whereby said switch can select and operatively connect but one of said sockets and heating element at any time.

4. In an electric tray, the combination of a body portion, an electrical heating element supported by said body portion, electrical outlet sockets supported by said body portion, two electrical supply conductors, a first electrical switch having spaced active contacts, first electric wires selectively connecting said active contacts with one terminal or each of said sockets and of said heating element, second electric wires connecting the other terminals of said sockets and'of said heating element with a first one of supply conductors and also connecting the other of said supply conductors with said switch, whereby said switch can select and operatively connect but one of said sockets and heating element at any time, said heating element including a high heat portion connected with said first switch and also a low heat portion, a second electrical switch, and third electric wires connecting said low heat portion and said second switch with said supply conductors, thereby controlling the operation of said low heat portion by said second switch.

5. In an electric tray. the combination of a body portion, an electrical outlet socket carried by said body portion and opening upwardly, and an electrically heated utensil having vertically disposed connection plugs in its lower portion for connection with said socket by downward movement of said utensil over said socket to rest upon said body portion, said socket having angular movement relatively to said body portion, whereby with said utensil on said body portion with its plugs in said socket, said utensil may have angular movement around the axis of said socket.

EDBON O. SESSIONS. 

